“Performance Paradigm I: Carcass Gain”
by Chris Reinhardt, feedlot specialist
Consider dressing percentage. All the old generalities still apply: steers dress higher than heifers, fed cattle higher than cows, beef breeds higher than dairy breeds, the average dressing percent of fed beef cattle is 62-64%. But what is the dressing percentage of the last pound of gain put on in the feedlot?
Here’s the deal: a fed steers walks into the pen with the greatest percentage of the head, hide, hooves, horns, and offal he’ll walk out of that pen with after 150 or 200 days on feed. So is he gaining 4 lbs per day of head, hide, hooves, horns, or offal? No, he’s putting on mostly muscle and fat—most of which winds up on the carcass, not on the floor (so-to-speak). So what’s the dressing percentage of that gain?—it’s fairly high. Some serial slaughter studies suggest that over 80% of the live weight gained at the end of the feeding period is carcass; that is, if a steer is gaining 3.0 lbs per day live, he’s also gaining 2.4 lbs of carcass daily.
Why does it matter? Because that mountain of performance data we’ve been collecting for the past few decades is potentially misleading, if you’ve switched to marketing on either a carcass weight or carcass value (grid) basis. The information is still true, but it no longer reflects the true relationship between the cost of gain and the value of gain. The cost of gain should now be calculated as daily cost over daily CARCASS gain, not daily LIVE gain, and the value of gain should be considered equal to the daily CARCASS cutout value, not the LIVE price.
The take home message is that cattle continue to gain carcass weight efficiently even at the end of the feeding period, after live efficiency would indicate that feeding is no longer cost effective. As a rule, when cattle approach yield grade 4 the increasing fat content of gain causes overall gain to slow and makes cost of carcass gain inefficient. But up until that point, remember that about 80% of all gain is going onto the carcass and feeding deep into yield grade 3 can be cost effective.
So if you’re a carcass-based seller, re-evaluate your marketing window based on value and cost of carcass gain, rather than value and cost of live gain.
